1 //===----------------------------------------------------------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is dual licensed under the MIT and the University of Illinois Open
6 // Source Licenses. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9
10 // <numeric>
11 // UNSUPPORTED: c++98, c++03, c++11, c++14
12
13 // template<class InputIterator, class T>
14 // T reduce(InputIterator first, InputIterator last, T init);
15
16 #include <numeric>
17 #include <cassert>
18
19 #include "test_iterators.h"
20
21 template <class Iter, class T>
22 void
test(Iter first,Iter last,T init,T x)23 test(Iter first, Iter last, T init, T x)
24 {
25 static_assert( std::is_same_v<T, decltype(std::reduce(first, last, init))> );
26 assert(std::reduce(first, last, init) == x);
27 }
28
29 template <class Iter>
30 void
test()31 test()
32 {
33 int ia[] = {1, 2, 3, 4, 5, 6};
34 unsigned sa = sizeof(ia) / sizeof(ia[0]);
35 test(Iter(ia), Iter(ia), 0, 0);
36 test(Iter(ia), Iter(ia), 1, 1);
37 test(Iter(ia), Iter(ia+1), 0, 1);
38 test(Iter(ia), Iter(ia+1), 2, 3);
39 test(Iter(ia), Iter(ia+2), 0, 3);
40 test(Iter(ia), Iter(ia+2), 3, 6);
41 test(Iter(ia), Iter(ia+sa), 0, 21);
42 test(Iter(ia), Iter(ia+sa), 4, 25);
43 }
44
45 template <typename T, typename Init>
test_return_type()46 void test_return_type()
47 {
48 T *p = nullptr;
49 static_assert( std::is_same_v<Init, decltype(std::reduce(p, p, Init{}))> );
50 }
51
main()52 int main()
53 {
54 test_return_type<char, int>();
55 test_return_type<int, int>();
56 test_return_type<int, unsigned long>();
57 test_return_type<float, int>();
58 test_return_type<short, float>();
59 test_return_type<double, char>();
60 test_return_type<char, double>();
61
62 test<input_iterator<const int*> >();
63 test<forward_iterator<const int*> >();
64 test<bidirectional_iterator<const int*> >();
65 test<random_access_iterator<const int*> >();
66 test<const int*>();
67 }
68